title: Clinical research in surgical oncology: an analysis of ClinicalTrials.gov.
abstract: BACKGROUND
  The objective of this study was to provide a descriptive analysis of registered clinical trials in surgical oncology at ClinicalTrials.gov.
  
  
  METHODS
  Data was extracted from ClinicalTrials.gov using the following search engine criteria: "Cancer" as Condition, "Surgery OR Operation OR Resection" as Intervention, and Non-Industry sponsored. The search was limited to Canada and the United States and included trials registered from January 1, 2001 to January 1, 2011.
  
  
  RESULTS
  Of 9,961 oncology trials, 1,049 (10.5%) included any type of surgical intervention. Of these trials, 125 (11.9%, 1.3% of all oncology trials) assessed a surgical variable, 773 (73.7%) assessed adjuvant/neoadjuvant therapies, and 151 (14.4%) were observational studies. Of the trials assessing adjuvant therapies, systemic treatment (362 trials, 46.8%) and multimodal therapy (129 trials, 16.7%) comprised a large focus. Of the 125 trials where surgery was the intervention, 59 trials (47.2%) focused on surgical techniques or devices, 45 trials (36.0%) studied invasive diagnostic methods, and 21 trials (16.8%) evaluated surgery versus no surgery. The majority of the 125 trials were nonrandomized (72, 57.6%).
  
  
  CONCLUSIONS
  The number of registered surgical oncology trials is small in comparison to oncology trials as a whole. Clinical trials specifically designed to assess surgical interventions are vastly outnumbered by trials focusing on adjuvant therapies. Randomized surgical oncology trials account for <1% of all registered cancer trials. Barriers to the design and implementation of randomized trials in surgical oncology need to be clarified in order to facilitate higher-level evidence in surgical decision-making.
authors.affiliation: Division of General Surgery, Department of Surgery, University of Ottawa, Ottawa, ON, Canada.
authors.forename: Amber S
authors.initials: AS
authors.lastname: Menezes
authors.forename: Alison
authors.initials: A
authors.lastname: Barnes
authors.forename: Adena S
authors.initials: AS
authors.lastname: Scheer
authors.forename: Guillaume
authors.initials: G
authors.lastname: Martel
authors.forename: Husein
authors.initials: H
authors.lastname: Moloo
authors.forename: Robin P
authors.initials: RP
authors.lastname: Boushey
authors.forename: Elham
authors.initials: E
authors.lastname: Sabri
authors.forename: Rebecca C
authors.initials: RC
authors.lastname: Auer
mesh_terms: D035843:Biomedical Research; D002986:Clinical Trials as Topic / Q000592:standards* / Q000706:statistics & numerical data*; D016208:Databases, Factual; D006801:Humans; D008495:Medical Oncology; D009369:Neoplasms / Q000601:surgery*; D011379:Prognosis